Shelly Mullenix began at LSU in 1997 as part of the LSU Athletic Training Staff, coming to Baton Rouge from Florida State, where she worked as a graduate assistant athletic trainer from 1992-1993. She was promoted to assistant athletic trainer at FSU in 1993 and served in that capacity until December 1996.

As LSU's senior associate athletic trainer, Mullenix plays a key role in servicing the athletic training needs of the football team on a day-to-day basis. She also serves the Department of Kinesiology as a clinical supervisor for the Athletic Training Education Program.

In addition to Mullenix's role as an athletic trainer with the Football program, she also was given the title of director of wellness in the spring of 2009. As the director of wellness, Mullenix's duties are very diverse. She serves as the athletic training liaison to the Athletic Department Assistance Program (ADAP) which helps to maintain the physical and psychological well-being of the student-athlete and is the athletic training liaison to the Academic Center for Student-Athletes, assisting in the identification and treatment of academic and behavioral issues. She works collaboratively with the Athletic Department's sports dietitians by working with the student-athletes in providing nutritional guidance given in both team format, as well as one-on-one individualized counseling. Administratively, she assists with the recruitment of athletic training students, serves as co-coordinator of graduate athletic trainer development, and provides leadership and guidance in the development of athletic training administrative policies.

Mullenix also owns Integrated Sports Management, LLC, a consulting company that provides a unique system of program administration, integrating four critical components of successful collegiate athletics: drug testing, mental health services, peer leadership and proper nutrition. Through ISM, Mullenix has consulted with several Division I programs and worked three seasons as a contracted consultant for the Miami Dolphins providing support services in the area of nutritional and psychological consultation.

She is married to Matthew Mullenix and has twin daughters, Maggie and Briana.